Banca de DEFESA: GUILHERME VINICIUS GONÇALVES DE PÁDUA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : GUILHERME VINICIUS GONÇALVES DE PÁDUA
DATA : 16/02/2017
HORA: 13:00
LOCAL: Auditório do CVT
TÍTULO:

VIABILITY AND VIGOR OF Acacia mangium WILLD. SEEDS IN DIFFERENT STORAGE ENVIRONMENTS 

PALAVRAS-CHAVES:

Deterioration; Longevity; Physiological quality.

 

PÁGINAS: 38
GRANDE ÁREA: Ciências Agrárias
ÁREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
ESPECIALIDADE: Sementes Florestais
RESUMO:

The primary challenge of seed storage is the maintenance of the physiological quality obtained from harvest to sowing. The main environmental factors that affect seed quality during this period are the temperature and the relative humidity of the air. The objective of this research was to evaluate the physiological and biochemical changes in Acacia mangium seeds in different storage environments. For this purpose, the seeds were stored in semipermeable polyethylene bags under three conditions: freezer (T = -20 ± 3 ° C, RH = 49%), domestic refrigerator (T = 6 ± 3 ° C, RH = 55%) and heated room T = 27 ± 4ºC, RH = 56%), with evaluations performed in the periods of 0 (control - initial quality before storage), 3, 6, 9, 12 and 15 months. For each evaluation period, the following determinations and tests were performed: water content (%), germination (%), first germination count (%), germination speed (VG), seedling dry mass %), Mean time of emergence (TME-days), total soluble sugars (μmol of AST g-1 MS), non-reducing sugars (μmol of ANR g-1 MS), total free amino acids (μmol of AALT g-1 MS ), Starch (mg g-1 seed glucose) and soluble proteins (mg g PS-1 MS). The experimental design was completely randomized, organized into a subdivided plots scheme, the main plot being the environment (3 levels) and the subplots, storage periods (6 levels). Four replicates of 100 seeds were used for the physiological variables and 5 replicates of 15 seeds (± 200 mg) for the biochemical variables. Seeds of A. mangium remained viable for 15 months and vigor for 12 months when stored in a freezer (T = -20 ± 3 ° C, RH = 49%), domestic refrigerator (T = 6 ± 3 ° C, RH = 55%). And air-conditioned room (T = 27 ± 4ºC, RH = 56%). The changes of physiological quality reduction in A. mangium seeds during short-term storage (6 months) is more pronounced for those kept in the freezer (T = -20 ± 3ºC, U.R. = 49%). For all the conditions tested, the decrease of the starch, AST and ANR contents throughout the storage is not clearly observed. In the 3 environments tested there was an increase in the contents of PS and AALT throughout the storage. It was not possible to explain physiological changes between the 3 storage conditions by carbohydrate reserve degradation mechanisms.

MEMBROS DA BANCA:
Interno - 1880265 - MARCIO DIAS PEREIRA
Presidente - 1721230 - MAURO VASCONCELOS PACHECO
Externo à Instituição - RISELANE DE LUCENA ALCÂNTARA BRUNO - UFPB